I think pollution is a key word here. CO2 is not a pollutant. It is no more a pollutant than O2 or H2O. It is a natural and required part of the atmosphere.

But if you want to take it to that extreme, any single gas in the air can be dangerous to the public health in high enough concentrations. Which means the government could micromanage how much you water your lawn (above and beyond water shortages), how much you sweat, and even how often you are allowed to breath.